package com.order.utils;


import cn.hutool.core.date.DateUtil;
import cn.hutool.core.util.StrUtil;
import com.auth0.jwt.JWT;
import com.auth0.jwt.algorithms.Algorithm;
import com.order.dao.User;
import com.order.mapper.UserMapper;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import javax.annotation.PostConstruct;
import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import java.util.Date;

@Slf4j
@Component
public class TokenUtils {
    private static UserMapper staticUserMapper;

    @Resource
    UserMapper userMapper;

    @PostConstruct
    public void setUserService(){
        staticUserMapper = userMapper;
    }
    /*    生成 token */
    public static String createToken(String userId, String sign){
        return JWT.create().withAudience(userId) // 将user id 保存到 token 中
                .withExpiresAt(DateUtil.offsetHour(new Date(),2)) //2小时候 token 过期
                .sign(Algorithm.HMAC256(sign)); // 以 password 作为 token 的秘钥
    }
    /*
      获取当前登录的用户信息
       return user对象
       */
    public static User getCurrentUser(){
        try {
            HttpServletRequest request = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getRequest();
            String token = request.getHeader("token");
            if(StrUtil.isNotBlank(token)){
                String userId = JWT.decode(token).getAudience().get(0);
                return staticUserMapper.getById(Integer.parseInt(userId));
            }
        }catch (Exception e){
            return null;
        }
        return null;
    }
}
